Covers for transport containers, as found in or used with trucks, trailers and other transport vehicles, are necessary for many reasons. For example, such covers reduce the likelihood that the load being carried escapes, and also protect the load from the elements. These covers are commonly housed at the front of the container in a cover assembly, and are pulled over the container. Often the covers are large and heavy, and therefore manipulating them manually is very difficult. Accordingly, various automated systems for manipulating transport container covers have been developed.
Some existing systems for manipulating truck container covers include telescopic arms deployed on opposite sides of the container to be covered, and attached at the ends of the cover. These arms are used to extend the cover over, and remove it from, the top of the container. Such systems may deploy the cover by extending the telescopic arms along the sides of the container.
Other existing systems may use a gantry assembly to manipulate a container cover. These assemblies often support a cover assembly used for cover deployment, and are usually mounted behind the cab of a vehicle. During cover deployment, the gantry assembly lifts the cover assembly above the container top, and the cover is extended across the container by, for example, a pullrope attached thereto. The cover is fastened at the back of the container, and the gantry assembly is lowered to bring the cover down over the load.
While generally effective, covering systems with side mounted arms may not be appropriate for all situations. For example, when a container being covered must be maneuvered in a relatively small area, the amount of clearance beyond the sides of the transport container may be minimal. In that circumstance, arms disposed beyond the sides of the container limit the maneuverability of the transport vehicle. Side mounted arms are also relatively expensive, and are susceptible to damage from inadvertent contact with walls or other vehicles.
Covering systems using gantry assemblies also have their shortcomings. These systems typically have a lift mechanism that is not mounted or fixed with respect to the truck body or container such that the entire mechanism rises concurrently with the gantry assembly. Use of these lift mechanisms, and their associated components, increases both maintenance and operation costs because of the greater number of moving parts. Safety is another concern for such systems as additional moving parts increase the likelihood that an operator may be pinched or the like. Furthermore, these systems often provide limited clearance above the load of a transport container. Poor clearance may lead to damage to the gantry assembly, and the cover itself when it comes in contact with the container load during deployment.